Study on the Microstructure and Wear Resistance of WC10Co4Cr Coatings Sprayed by Miniaturized HVOF Equipment for Narrow Spaces of Hydroturbine

• Published in: Cai liao bao hu Vol. 58; no. 8; pp. 162 - 171
• Main Author: XIE Changning, ZHANG Lu, LIU Gang, LI Yi, QIN Yuze, XIE Weiwei
• Format: Journal Article
• Language: Chinese
• Published: Editorial Department of Materials Protection 01.08.2025
• Subjects: supersonic flame spraying；miniaturized hvof equipment；wc10co4cr coating；hydroturbine；narrow space spraying；microstructure；wear resistance
• ISSN: 1001-1560
• DOI: 10.16577/j.issn.1001-1560.2025.0144

In order to address the issue of small angle spraying and low efficiency in the preparation of hard metal coatings in narrow spaces such as hydroturbine blades due to the large size of the gun head of commercial high velocity oxygen fuel (HVOF) equipment，a miniaturized HVOF system was developed.WC10Co4Cr hard metal coatings were prepared under different spraying angles using this miniaturized system.The effects of spraying angle on the coating’s microstructure，surface roughness，microhardness，bonding strength and abrasive wear resistance were investigated using scanning electron microscopy (SEM)，laser confocal microscopy，digital microhardness tester，universal material testing machine，and rubber wheel abrasive wear tester.These results were compared with coatings prepared using commercial HVOF equipment.Results showed that the phase composition of WC10Co4Cr coatings produced by both equipment types was similar，with WC as the primary phase，along with W2C and W phases produced due to the decomposition of WC.The p